A new project called GoFlow wants to bring neurostimulation to the masses. Michigan State University PHD student Benjamin Syzek is currently working on a DIY transcranial direct current stimulation (TDCS) kit that will let anyone build and operate a TDCS machine for only $99. TDCS stimulates the brain by delivering low currents through electrodes placed on the head, and research suggests that it can have a number of positive effects, including improving memory and learning ability. However, as the GoFlow site points out, TDCS machines are typically expensive and require a prescription, and it's still unclear what kind of long term effects the process might have.
It probably doesn't sound like the kind of thing you'd want to try on your own brain, especially unsupervised. And the fact that the GoFlow team describes its kit — which is still in the prototyping phase — as "the shit" doesn't make us any more confident. But if you're intent on sending electrical currents to your brain in the least expensive way possible, you can sign up on the GoFlow site to be notified on when the actual product will launch — or you could just snag a cheap taser and not have to worry about the whole building it yourself part.